A poll was conducted to determine what percentage of the peoplesupport a certain candidate for the U.S. Senate.400 people were surveyed, and44% of them said they support thecandidate. If we require a confidence level of99%, what margin of error do we report?

Respuesta :

Answer: 0.064

Step-by-step explanation:

The formula to find the margin of error :-

[tex]E=z_{\alpha/2}\sqrt{\dfrac{p(1-p)}{n}}[/tex]

Given : Significance level : [tex]\alpha=1-0.99=0.01[/tex]

Critical value : [tex]z_{\alpha/2}=2.576[/tex]

Sample size : n=400

The proportion of people support the candidate :p=0.44

Then , [tex]E=(2.576)\sqrt{\dfrac{0.44(1-0.44)}{400}}\approx0.064[/tex]

Hence, Margin of error = 0.064